Brief Summary

This study is organized as multi-center single (patient)-blinded randomized controlled trial. There are two treatment groups involved in the trial, the investigational group and the active control group.

The aim of this trial is to evaluate if P-15 bone putty (investigational device) is not inferior in effectiveness and safety to local autologous bone (control device) when applied in instrumented anterior cervical discectomy and fusion (ACDF) with use of a structural allograft ring in patients with degenerative cervical disc disease.

This study will follow up patients until the last subject reaches the 24 month follow-up or until the study meets the pre-determined statistical stopping rules (interim analysis or sample size re-estimation), which includes annual visits up to 6 years until the last patient enrolled has completed the 24 month visit.

Detailed Description

Degenerative disc disease (DDD) of the cervical spine can result in significant pain, instability, and radiculopathy and/or myelopathy. These symptoms are due to loss of disc space height, loss of foraminal area, disc bulging or protruding osteophytes causing neural compression. Cervical DDD is treated conservatively; when conservative treatment fails, surgical treatment is an option. The goals of surgical treatment are decompression of spine/nerve root, restoration of cervical alignment, and stability. Decompression involves discectomy (removal of the soft disc) and/or removal of osteolytic structures. Restoration of alignment involves restoration of the disc space height and neural foraminal height. Stability involves elimination of motion in order to induce resorption of posterior osteophytes. Instrumented fusion is the current standard of care for surgical treatment of cervical disc disease in the US. The standard approach is anterior surgery. Support to the treated segment is achieved by using a structural device such as an allograft ring. Anterior cervical plating is commonly used to provide additional stability to the segment of the spine to which it is applied and maintain spinal alignment, prevent graft dislodgement and collapse, enhance fusion rates, and eliminate the need for external immobilization. The void space in the allograft ring can be filled with autologous bone or various bone replacement materials to improve the fusion process and clinical outcomes. Although autologous bone achieves good results, it is associated with additional morbidity. The autologous bone can originate from local millings and osteophyte bone or from harvesting iliac crest bone. Harvesting iliac crest is associated with donor site pain and morbidity and is currently rarely applied in the US clinical practice. The most frequently reported problems associated with harvesting iliac crest autologous bone include postoperative pain, wound hematoma, infection, pelvic fracture, nerve palsy, and chronic donor site pain. The complications and donor site morbidity in autograft applications have intensified the search for various forms of bone replacement materials as alternatives for use in cervical interbody fusion.
P-15 bone putty is a synthetic osteoconductive bone substitute that has proven to significantly improve bone repair in dental applications. Advantages of P-15 bone putty are its synthetic preparation and lower costs compared to alternatives. Effectiveness and safety of P-15 bone putty for surgical treatment of degenerative cervical disc disease have not been rigorously evaluated.

Contact Information

•Radiographically determined discogenic origin to include at least one of the following characteristics: Degenerated/dark disc on MRI, decreased disc height compared to adjacent levels on radiographic film, CT, or MRI, and disc herniation on CT or MRI;

•Radicular symptoms by history and physical exam to include at least one of the following characteristics: Arm/shoulder pain, decreased reflexes, decreased strength, and abnormal sensation;